In connection with a motor vehicle, a brake, of course, is any mechanical device for arresting the motion of a wheel (and accordingly the vehicle) by means of friction. Kinetic energy is converted into heat energy through use of frictional forces applied to the wheels of the vehicle, causing the vehicle to slow or stop. A drum brake is a type of brake using a drum-shaped metal cylinder attached to the inner surface of the wheel of a motor vehicle and rotating within it. When the brake is applied, curved brake shoes with friction linings press against the drum's inner circumference to slow or stop the vehicle. The rotating part of a disc brake is also called a “rotor.” The nonrotating, basically stationary, component of a disc brake system is a brake caliper that applies force from a hydraulic system to the rotor or disc to decelerate and stop a vehicle.
Brake fade is a condition brought about by repeated or protracted braking that results in reduced braking effectiveness (fading). Heat is the primary cause of brake fade, which in turn causes expansion and other undesirable thermal effects on a brake. Although disc brakes are less prone to fade because rotors are more effectively cooled by air moving across the brakes, and can be internally vented to increase resistance to fade, nevertheless persistent stop-and-start braking causes damage to any brake, whether a drum or rotor. Accordingly, a significant industry has developed in connection with the machining, refinishing, balancing and resurfacing of brake rotors.
To refinish a brake, a drum or a rotor is mounted on the shaft or arbor of a brake lathe system. During operation, forces due to rotation and gravity tend to preclude uniform rotation of the rotating arbor on which a brake has been mounted. The arbor and devices mounted on the arbor for refinishing do not rotate in a single, unvarying plane of rotation. The forces acting on a rotating arbor and brake may distort in one or more planes and along one or more axes of rotation. The forces exert a variety of angular and planar forces that affect how accurately and quickly the brake lathe operator may work on a brake to refinish it.
In addition, forces and force vectors may induce harmonics and vibrations that may be transmitted to the arbor, brake and other components of the lathe. A nonuniform rotation of a brake during a refinishing operation may cause a cutting tool brought into contact with a brake surface to produce an inferior surface.
To overcome such undesirable problems, the inventor named in this document has received a number of U.S. patents for apparatus and methods that resolve in an exemplary fashion adverse consequences of such forces, thus improving the refinishing process, including U.S. Pat. No. 6,279,919B1 issued Aug. 28, 2001 for an Apparatus for Securing a Workpiece to a Rotatable Machine Member; U.S. Pat. No. 6,554,291B1 issued Apr. 29, 2003 for an Apparatus for Securing a Workpiece to a Rotatable Machine Member; U.S. Pat. No. 6,397,989B1 issued on Jun. 4, 2002 for an Apparatus for Reducing Harmonics and Vibrations of a Rotatable Base Piece; U.S. Pat. No. 6,631,660B1 issued Oct. 14, 2003, for a Self-Aligning Arbor Nut System. The inventor currently has pending a U.S. patent application for a Multi-angle Cutting Head, application Ser. No. 10/684,021 filed on Oct. 10, 2003. The patents and application are collectively referred to in this document as the “Prior Patents”.
The apparatus and method described and claimed in this document add to the art by providing a reversible flange plate that reduces costs associated with refinishing a rotor by providing on one apparatus differently configured surfaces that allow an operator to reverse the orientation of the reversible flange plate to engage a variety of differently configured brakes. The multiple applications of the reversible flange plate during operation allow an operator to purchase the single flange plate that replaces a number of single-sided flange plates. In addition, the reversible flange plate is easy to assemble on a brake lathe, and easy to operate. The reversible flange plate allows the operator of the brake lathe to produce a more accurately and precisely machined, turned and resurfaced brake. In combination with the apparatus and methods shown in the Prior Patents, undesirable forces that affect refinishing of a brake are reduced or eliminated. The reversible flange plate also is simple to reposition. By eliminating flange plates and adapter plates from the array of plates customarily required to refinish a brake, the reversible flange plate reduces the costs of manufacture, the costs associated with operating a brake lathe, and is respectively easy to use and to practice for its intended purposes.